The present invention relates to a gymnastic bicycle which is designed so that the user can practice different physical exercises.
One of the objects of the invention is to provide the gymnastic bicycle with a vibrating mechanism, the main element of which comprises a polygonal shaped member mounted on the pedal shaft of the bicycle, whereby the vibration produced by such member is transmitted through suitable means to the handlebar of the bicycle.
Another object of the invention is to provide the gymnastic bicycle with a friction device having an adjustable resistance, the purpose of which is to adjust the physical force required by the user during those type of exercises which resemble rowing, which takes place by using the handlebar itself of the bicycle.
A further object of the invention is to provide the bicycle with a device which, joined to the main vibrating mechanism, permits the vibrations produced when pedalling to be transmitted to the abdomen of the user.
A final object of the invention is to provide the bicycle with another device, also joined to the main vibrating mechanism, whereby the vibrations are transmitted to the lumbar region of the user.
Therefore, with the gymnastic bicycle of the invention the user can practice physical exercise resembling rowing and which will be carried out by using the handlebar itself of the bicycle, while if the user practices the physical exercise of pedalling, vibrations will be produced and will be transmitted, through the handlebar itself and the previously mentioned devices joined to the main vibrating mechanism, to the abdomen and lumbar region of the user.
The friction device having an adjustable resistance, the purpose of which is to adjust the physical force to be employed by the user during exercises resembling rowing which are carried out by using the handlebar, is so designed that the device itself permits the handlebar to be oscillated about a transverse axis, the oscillation of the handlebar produced by the user with his own effort.
The resistance to such oscillation is adjustable depending on the amount of force or the degree of preparation which the user desires to apply in his exercises. The device basically includes an axle joined to the lower end of the tubular piece or stem which supports the handlebar, which axle is disposed transversely and is capable of oscillating about its own axis. The complete assembly of the handlebar is capable of producing displacements in the longitudinal direction of the frame of the bicycle due to the articulated mounting of the axle. The inner walls of the axle are formed to have truncated sections forming sliding and friction surfaces for corresponding sleeves or truncated pieces which fit therein. Tightening means are joined to the general chassis of the bicycle and form elements for achieving a greater or lesser resistance to the rotation of the axle and, consequently, to the oscillating movements of the handlebar to resemble the gymnastic exercises of rowing.
Therefore, the friction device having an adjustable resistance has a simple construction, can readily be mechanized and provides an optimum functioning, effectiveness and accuracy with regard to the purposes for which it is designed.
The main vibrating mechanism includes a thick projection extending radially backwardly from the axle of the friction device. This projection is provided with a transverse hole to receive a pin acting as a freely rotating shaft for a connecting rod which, at its opposite end, is joined by means of a transverse pin to a roller which is slidable along outer surfaces of the polygonal member forming the main element of the vibrating mechanism. The connecting rod is hinged to the projection of the axle at a lateral zone of the end of the connecting rod. Opposite to such zone the end of the connecting rod expands into a large concave curved surface the radius of curvature of which coincides with that of the outer surface of the axle, against which surface it bears in an operative position.
The roller is in permanent contact with the outer surfaces of the polygonal member due to the traction of a spring which joins the connecting rod to the frame of the bicycle. Thus, when the pedal shaft is rotated by the pedals, the polygonal member will rotate. Since the roller is permanently in contact with the polygonal member, vibrating movements will be imparted to the handlebar itself, and such movements will be transmitted to the body of the user and more specifically on the abdomen of the user.
In the event that the vibrating mechanism is to be rendered inoperative, so that the bicycle can perform other functions, there is disposed on the projection a screw provided with a driving head, which screw is mounted on the frame of the bicycle. Thus, when such screw is moved axially, the end thereof will push the projection, whereby the axle will make a partial turn. This pushing or oscillation of the projection moves therewith the articulation pin of the connecting rod such that the curved concave surface of the connecting rod moves away from the surface of the axle. Thus, the transmission of vibration is interrupted.
The polygonal member joined to the pedal shaft and along which the roller of the connecting rod slides is formed by deformation of a sprocket wheel, to form therein a prismatic-polygonal recess.
The device joined to the main vibrating mechanism and which permits the transmission of vibration towards the abdomen of the user hereinafter will be referred to as the abdominal vibrating device. Such abdominal vibrating device includes a bar having one end connected to the central zone of the handlebar. The opposite end of the bar prolongs into a fork between the free ends of which is retained a flexible transverse band which may be adapted to the abdominal region of the user. This device permits the vibrations produced in the main vibrating mechanism to be transmitted to the abdominal region of the user. The abdominal vibration mechanism furthermore has the important advantage that it can adopt different lengths since the bar which is connected to the central zone of the handlebar is formed of two telescopically connected tubes.
The device likewise joined to the main vibrating mechanism and which permits the vibrations originated by the main vibrating mechanism to be transmitted to the lumbar region of the user, hereinafter will be referred to as the lumbar vibrating device. Such lumbar vibrating device includes a band made of a flexible fabric material which is designed to clasp the lumbar region of the user. This band is subjected to a rate of vibrations which is determined by the user himself, depending on the pace at which he pedals. The band of fabric material is mounted between the arms of a Y-shaped fork having a telescopic vertical shaft, a lower arm of which is slightly bent and the lower end of which is positioned adjacent the polygonal member secured to the pedal shaft. At such lower end is rotatably mounted a roller which is in contact with the polygonal member. During rotation of the member, the roller will be subjected to a series of blows which will be transmitted, through the fork, to the band of fabric material. This transmission of blows will take place in the form of mechanical vibrations which will impart to the user a highly therapeutic massage.